Tips on Surge Protective Devices (SPD)
The following was copied, er, “repurposed” from a recent newsletter from my insurance company, State Farm. I was thinking I'd file this away for the next time I was looking for such a device, instead I figured I'd blog about it so I can google myself later. Any comments or other tips welcome.
When purchasing an SPD, look for the following characteristics:
- The device needs to be UL listed 1449 2nd edition or approved by the CSA.
- The clamping voltage should be less than 400 volts for sensitive electronic equipment, 800 volts or less for “whole house“ devices.
- Look for SPDs with a manufacturer's warranty. Some warranties cover the device; others also cover the damaged equipment.
- Any equipment that connects to the phone line (such as a telephone or computer modelm) or to an antenna/coaxial cable (such as a TV, Satellite receiver or cable modem) must use an SPD that is design to protect against surges that may enter the home on these connections.
- SPDs have a limited life span. The surge protecture must have some means of letting the user know it has failed and is no longer protecting the connected equipment.
- Do not rely on the joule rating as a measure of performance. The methods used to establish the joule rating may vary widely from manufacturer to manufacturer.